title: Fabrication of CuInS2 films from electrodeposited Cu/In bilayers: effects of preheat treatment on their structural, photoelectrochemical and solar cell properties.
abstract: Polycrystalline CuInS(2) films were fabricated by sulfurization of electrodeposited Cu and In metallic precursor films in a Cu-rich composition at 520 °C in H(2)S (5% in Ar). Structural analyses revealed that the adherence of the thus-formed CuInS(2) film to the Mo substrate was strongly dependent on heating profiles of the Cu/In bilayer film: a CuInS(2) film with poor adherence having many crevices was formed when the Cu/In bilayer film was heated monotonously from room temperature to 520 °C in Ar within 25 min followed by sulfurization, whereas CuInS(2) films with good adherence were obtained when the Cu/In films were pretreated at 110 °C in Ar for 10-60 min just before increasing the temperature up to 520 °C for sulfurization. It was also clarified that the CuInS(2) film obtained without 110 °C pretreatment had pinholes inside the film, whereas the CuInS(2) films formed after 110 °C pretreatment showed no notable pinholes. Photoelectrochemical responses of these CuInS(2) films in an electrolyte solution containing Eu(III) indicated that the CuInS(2) films obtained after 110 °C pretreatment had higher external quantum efficiency (EQE) values than those of films obtained without 110 °C pretreatment, mainly due to better adherence of 110 °C pretreated CuInS(2) films to the Mo substrate than the CuInS(2) film obtained without 110 °C pretreatment. The performance of solar cells with an Al:ZnO/Zn(S,O)/CdS/CuInS(2)/Mo structure also depended on the structural characteristics of the CuInS(2) films, i.e., preliminary conversion efficiencies of ca. 5% were obtained for devices based on the CuInS(2) films obtained after 110 °C pretreatment, whereas the device prepared by the CuInS(2) film without 110 °C pretreatment showed the conversion efficiency less than 1.5%.
authors.affiliation: Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
authors.forename: Sun Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Shigeru
authors.initials: S
authors.lastname: Ikeda
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Yagi
authors.forename: Takashi
authors.initials: T
authors.lastname: Harada
authors.forename: Ahmed
authors.initials: A
authors.lastname: Ennaoui
authors.forename: Michio
authors.initials: M
authors.lastname: Matsumura
mesh_terms: D055598:Chemical Phenomena; D003300:Copper / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D004595:Electroplating; D006358:Hot Temperature; D007204:Indium / Q000737:chemistry*; D008982:Molybdenum / Q000737:chemistry; D055620:Optical Phenomena; D055668:Photochemical Processes; D012643:Selenium / Q000737:chemistry*; D012993:Solar Energy; D013455:Sulfur / Q000737:chemistry
chemical_list: C101793:copper indium diselenide; D007204:Indium; D013455:Sulfur; D003300:Copper; D008982:Molybdenum; D012643:Selenium